The city is getting ready for a potential 2027 start date on one of its biggest projects to address stormwater flooding in Lynhaven and the northern part of Del Ray.
The city held a meeting on the Commonwealth, Ashby, and Glebe Flood Mitigation Project last Thursday (June 4) at the Leonard “Chick” Armstrong Recreation Center. Since the last community meeting in 2025, the project has received final design plans, and the city is preparing to solicit a construction contractor. It is also coordinating with utility owners for utility relocation to accommodate new stormwater infrastructure. Summer 2027 is the tentative construction start date.
The project is one of several Flood Action Alexandria projects to address more frequent flash flooding from storms due to climate change. Insufficient stormwater capacity has been cited as an issue affecting inland flood-prone areas.
John Whiteleather, project manager for the Commonwealth, Ashby, and Glebe Flood Mitigation Project, said flooding results when stormwater pipes are full and inlets start to push water out.
“Two main areas at Commonwealth [Avenue] and Glebe [Road] and Ashby [Street] and Glebe experience increasingly frequent flooding in the project area,” Whiteleather said at the June 4 meeting. “Basically, the storm sewer is too small to handle the runoff draining to it … This is old infrastructure. The design criteria at the time of construction is not up to current standards, and we are starting to observe increasingly intense and frequent rainfall.”
The project will add new relief storm sewers along Commonwealth Avenue and E. Glebe Road for stormwater runoff. A new outfall being added at Four Mile Run will discharge increased stormwater flow. The city is also adding green infrastructure along Commonwealth Avenue medians to improve stormwater quality.
Construction will happen in phases over three and a half years. The project will start at the Four Mile Run outfall location and continue south along Commonwealth Avenue to Ashby Street for about two years. There will also be stormwater capacity work along E. Glebe Road from Commonwealth Avenue to Ashby Street for about a year followed by local improvements along Montrose Avenue from Ashby Street to Hume Avenue for about six months.
The schedule is subject to change based on timing of the contractor bid process and utility relocations.
During the project, drivers will encounter narrowed or closed lanes. The city will maintain resident access to buildings and access to at least one business driveway. Street parking will not be available during construction, and bike lanes will be closed. Some sidewalks and trails will be closed to pedestrians, and detours will be marked. The Four Mile Run Softball Field (North) will be closed throughout the project to serve as a construction staging area. Access to the new kayak launch at Four Mile Run will be maintained.
The project will also require some tree removals. Whiteleather said the team worked with the city’s urban forestry staff to identify trees that needed to be removed for the project, as well as unhealthy trees that staff requested be removed.” One private property will have roots removed that extend onto the project area.
Whiteleather couldn’t provide a count of trees being removed but said the rest will be on the public right-of-way. The project was designed with a bend along the culvert to preserve two large old trees along Commonwealth Avenue at Leadbeater Street.
“Trees are a very important part of this community, and there was a lot of effort to protect the trees as we approach design,” Whiteleather said. “However, some trees will have to be removed due to conflict with the proposed storm sewer or the utility relocations.”
As part of the project, invasive trees along Four Mile Run will be removed and will not be replanted in the outfall area due to the culvert’s depth. Native trees and shrubs will be replanted on the eastern side of Commonwealth Avenue from Four Mile Run to Reed Avenue.
Along the southern part of Commonwealth Avenue, trees on the median will be replaced with native trees, grasses and flowering perennials. Several trees along the boulevard strip bordering properties on Ashby Street will also be removed and not replanted due to a small buffer strip. Residents will be notified if a tree will be removed in front of their property.
During construction, crews will be conducting geotechnical monitoring to gauge the impact of vibrations and movement. Vibration monitors will be placed within 100 feet of active construction. Movement sensors will be placed every 60 feet in the active construction zone and more closely where there are structures and utilities.
“We’re going to be monitoring for a threshold below what would cause any damage, and basically what happens is that threshold is hit, work is stopped, and we identify the cause, and basically, once that can be corrected, we’ll restart construction,” Whiteleather said about the vibration monitoring.
The city will contact property owners by mail to offer voluntary pre-construction assessments on conditions before the project begins. The assessment will cover what visible cracks and visible settlement are present in walls, floors, ceilings and foundation, as well as conditions of exterior driveways, walkways, stairs, fences, porches and yards.
Potential construction impacts that could lead to claims include construction equipment hitting fences, equipment causing cracks on driveways and walkways and cracks caused by ground settlement or vibrations.
